From 685f605a498b73759cbcbc816089e804710fcc48 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 27 Aug 2008 22:35:56 -0700 Subject: [PATCH] pkt_sched: Fix return value corruption in HTB and TBF. [ Upstream commit 69747650c814a8a79fef412c7416adf823293a3e ] Based upon a bug report by Josip Rodin. Packet schedulers should only return NET_XMIT_DROP iff the packet really was dropped. If the packet does reach the device after we return NET_XMIT_DROP then TCP can crash because it depends upon the enqueue path return values being accurate. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_htb.c | 20 ++++++++++++-------- net/sched/sch_tbf.c | 11 ++--------- 2 files changed, 14 insertions(+), 17 deletions(-) diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c index 3fb58f428f7..51c3f686969 100644 --- a/net/sched/sch_htb.c +++ b/net/sched/sch_htb.c @@ -595,11 +595,13 @@ static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch) kfree_skb(skb); return ret; #endif - } else if (cl->un.leaf.q->enqueue(skb, cl->un.leaf.q) != + } else if ((ret = cl->un.leaf.q->enqueue(skb, cl->un.leaf.q)) != NET_XMIT_SUCCESS) { - sch->qstats.drops++; - cl->qstats.drops++; - return NET_XMIT_DROP; + if (ret == NET_XMIT_DROP) { + sch->qstats.drops++; + cl->qstats.drops++; + } + return ret; } else { cl->bstats.packets += skb_is_gso(skb)?skb_shinfo(skb)->gso_segs:1; @@ -639,11 +641,13 @@ static int htb_requeue(struct sk_buff *skb, struct Qdisc *sch) kfree_skb(skb); return ret; #endif - } else if (cl->un.leaf.q->ops->requeue(skb, cl->un.leaf.q) != + } else if ((ret = cl->un.leaf.q->ops->requeue(skb, cl->un.leaf.q)) != NET_XMIT_SUCCESS) { - sch->qstats.drops++; - cl->qstats.drops++; - return NET_XMIT_DROP; + if (ret == NET_XMIT_DROP) { + sch->qstats.drops++; + cl->qstats.drops++; + } + return ret; } else htb_activate(q, cl); diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c index 0b7d78f59d8..fc6f8f33ac6 100644 --- a/net/sched/sch_tbf.c +++ b/net/sched/sch_tbf.c @@ -123,15 +123,8 @@ static int tbf_enqueue(struct sk_buff *skb, struct Qdisc* sch) struct tbf_sched_data *q = qdisc_priv(sch); int ret; - if (skb->len > q->max_size) { - sch->qstats.drops++; -#ifdef CONFIG_NET_CLS_ACT - if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch)) -#endif - kfree_skb(skb); - - return NET_XMIT_DROP; - } + if (skb->len > q->max_size) + return qdisc_reshape_fail(skb, sch); if ((ret = q->qdisc->enqueue(skb, q->qdisc)) != 0) { sch->qstats.drops++; -- 2.11.4.GIT